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Very Confused

Daboss

By Daboss,
in Engines & Forced Induction

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Daboss Experienced

Daboss

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Posted

Hey forum I am at a stand still with my rebuild and just need some expert opinions to get going again. Ok here is the deal I am currently in the process of rebuilding my engine, lost the ring on number six so since it had to open up neway I decided to strengthen it up a bit. I just changed the head gasket to a thicker cometic one and got a set of forgies the wiseco 87mm, all the other little things are getting done as well (oil pump, water pump, tensioners, timing belt etc...,) and what I want to know is if its just as simple as boring out the block to fit the bigger pistons. My main reason for going bigger and forge was to get my monies worth out the rebuild and engine strength for when I fit a bigger turbo. The specs on the piston can be found here http://www.wiseco.com/PDFs/Catalogs/SC08/NissanSubaruToyotaVW.pdf and I just wanted to know if I will run into any problems fitting these pistons, will still be using all original engine parts only the head gasket and pistons will be changed. So can these pistons be fitted to the same conrods and crank do I have to worry bout squish and quench and all that other technical stuff I have been reading up on? I am not looking for any particular compression or trying to build a superior race engine just want to strengthen the engine a bit and get my car back on the road with a somewhat stronger engine. I just want to get it bored drop the pistons in with the new head gasket and close it up.Can this be done or willI have problems?

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TiTAN Grand Master

TiTAN

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So you want to make the engine stronger but you want to bore it out to 87mm? If something happens and the engine does have to be re bored you have to go custom pistons next time. Why not get 86.5mm pistons or even 86mm if the bores are still good?

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Daboss Experienced

Daboss

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So you want to make the engine stronger but you want to bore it out to 87mm? If something happens and the engine does have to be re bored you have to go custom pistons next time. Why not get 86.5mm pistons or even 86mm if the bores are still good?

I was thinking that as well but wiseco does not make 86mm for the rb25 only 86.5mm. If i were to get the 86.5mm it will still have to be bored so I just went with the 87 mm as I was thinking it will handle more boost and increase comp ratio a bit. Do you know of any compny that are affordable and have the rb25 standard size pistons forged?

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NYTSKY Grand Master

NYTSKY

Posted
Posted
So you want to make the engine stronger but you want to bore it out to 87mm? If something happens and the engine does have to be re bored you have to go custom pistons next time. Why not get 86.5mm pistons or even 86mm if the bores are still good?

Should have gone for the 86.5mm pistons.

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